Take the annual survey by the National Association of Chiefs of Police of more than 20,000 chiefs of police and sheriffs. In 2010 it found that 95% believed "any law-abiding citizen [should] be able to purchase a firearm for sport or self-defense." Seventy-seven percent believed that concealed-handgun permits issued in one state should be honored by other states "in the way that drivers' licenses are recognized through the country"—and that making citizens' permits portable would "facilitate the violent crime-fighting potential of the professional law enforcement community." . . .